/*
 * Copyright 2014, Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *    * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *
 *    * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package io.grpc;

/**
 * The call type of a method.
 */
public enum MethodType {
  /**
   * One request message followed by one response message.
   */
  UNARY,

  /**
   * Zero or more request messages followed by one response message.
   */
  CLIENT_STREAMING,

  /**
   * One request message followed by zero or more response messages.
   */
  SERVER_STREAMING,

  /**
   * Zero or more request and response messages arbitrarily interleaved in time.
   */
  DUPLEX_STREAMING,

  /**
   * Cardinality and temporal relationships are not known. Implementations should not make
   * buffering assumptions and should largely treat the same as {@link #DUPLEX_STREAMING}.
   */
  UNKNOWN;

  /**
   * Returns {@code true} if the client will immediately send one request message to the server
   * after calling {@link Call#start(io.grpc.Call.Listener, io.grpc.Metadata.Headers)} and then
   * immediately half-close the stream by calling {@link io.grpc.Call#halfClose()}.
   */
  public final boolean clientSendsOneMessage() {
    return this == UNARY || this == SERVER_STREAMING;
  }

  /**
   * Returns {@code true} if the server will immediately send one response message to the client
   * upon receipt of {@link io.grpc.ServerCall.Listener#onHalfClose()} and then immediately
   * close the stream by calling {@link ServerCall#close(Status, io.grpc.Metadata.Trailers)}.
   */
  public final boolean serverSendsOneMessage() {
    return this == UNARY || this == CLIENT_STREAMING;
  }
}
